After six months as anchor, Diane Sawyer is bringing a sharper edge to ABC's 'World News'

It is not yet 9 a.m. and Diane Sawyer is shaking her head in amazement.

"Unbelievable," she says, having woken up to the news that Gen. Stanley McChrystal had denigrated President Obama's team in a Rolling Stone piece. "Oh, my gosh, it had to have been off the record. . . . What do you do if you're the Obama White House?. . . . This is not the general we knew."

This is the non-glamorous side of Sawyer, who at the moment -- with her untamed hair, pale skin, black-rimmed glasses and plain white shirt -- looks like a 64-year-old housewife in need of a cup of coffee. She sits in a row of eight desks at ABC's Columbus Avenue newsroom, conducting a rolling conversation with her staff, peppering them with endless questions about the stories taking shape.

In six months as anchor of "World News," the longtime morning star hasn't changed the newscast's second-place status, but she has brought a sharper edge to the aging format. By pushing her reporters to brandish documents on the air and investigate e-mail questions from viewers, by complaining about official intransigence, she is forging what a top ABC executive calls an "advocacy" program.

"We've done quite a bit of making room for the extra thought -- allowing ourselves to tell you the one thing we found fascinating," Sawyer says. "It's become a real conversation we're having with you, that we would have if we were sitting in your living room. I think it gives us some freedom to be ourselves."

Sawyer's exacting standards don't end with the staff. She says she asks herself about each broadcast: "Is it as alive as it could be? Are you conveying your own sense of excitement and not falling into formulas?"

Jon Banner, the executive producer, calls Sawyer "the most curious person I've been around in a long time. She is constantly pushing us to ask the next question."

To avoid the overheated hoopla that surrounded Katie Couric's CBS debut in 2006, Sawyer succeeded Charlie Gibson in low-key fashion four days before Christmas, and her changes to the newscast have been slow and subtle. She has brief, unscripted exchanges with her reporters, and "World News" often shows them at their desks or interviewing people on the phone, rather than in traditional stand-ups.

"Jon Karl sitting in front of a computer saying, 'But it's right here on Page 4,078,' tells you many things," says Sawyer, recalling the reporter citing a provision of the health-care legislation. "It's a way of showing that what we're doing is not mysterious."

Sitting up stiffly, Sawyer explains: "I know our correspondents have long felt the formality of what we do -- 'This is what it is, back to you, thank you, turn' -- doesn't allow us to question things the way people at home question them."

Karl says Sawyer gives him constant feedback and urged him, on the health bill, to "dive into that thing and show us where it is and what you have found. . . . She has helped make me a better reporter. She has great antennae for questions that cut to the chase."